Conventional endoscopes commonly use a lens system to transmit the image from the distal tip of the endoscope to a viewer. The lens system is typically a relay lens system in the case of rigid endoscopes or a bundle of fiber optics or an objective lens system in the case of flexible endoscopes. In the case of both rigid and flexible conventional endoscopes, the lens or fiber optic system is relatively expensive and is intended to be re-used many times. Therefore, stringent decontamination and disinfection procedures need to be carried out after each use. Furthermore, known fiber endoscopes and rigid endoscopes have limited lens FOV of no more than 100 degrees, and typical conventional flexible digital endoscope FOV is no more than 120 degrees.
Disposable endoscopy is an emerging category of endoscopic instruments that lessen the risk of cross-contamination and hospital acquired diseases. Partially disposable endoscopy systems for hysteroscopy are discussed in U.S. Pat. No. 8,460,182, incorporated by reference herein. A hysteroscope having a disposable probe was offered by Endosee Corporation of Los Altos, Calif., and is now offered by CooperSurgical, Inc. of Trumbull, Conn., a company that acquired EndoSee Corporation. The endoscope has a miniature video camera at the tip of the disposable portion. The tip has a small diameter, which makes it difficult to incorporate a lens system. In the known disposable endoscope, the camera FOV is no more than about 120°, so the user may need to frequently reposition the tip to include different areas of the uterus in the camera FOV. For endoscopes that are suitable for larger or differently shaped organs, such as the bladder, viewing different areas of the bladder interior may require even more frequent repositioning of the camera tip with such an FOV. This is undesirable because it makes the examination longer, and also because it prevents the concurrent viewing of a larger area in the organ.
The endoscope tip includes light sources such as LEDs to illuminate at least a portion of the camera FOV. The illuminated field typically is not the same as the camera FOV, so that some of the camera FOV is not illuminated and thus is not imaged well and/or some of the illumination is wasted in that it does not contribute to imaging because it illuminates an area not currently seen by the camera. In addition, the illumination may impair imaging depending on the position and orientation of the camera relative to the organ being imaged. For example, if one set of LEDs is much closer to the organ wall than another set, one area of the wall can be illuminated more and can appear brighter and even saturate that area of the image, making image assessment more difficult.
The subject matter described or claimed in this patent specification is not limited to embodiments that solve any specific disadvantages or that operate only in environments such as those described above. Rather, the above background is only provided to illustrate one exemplary technology area where some embodiments described herein may be practiced.